Engraving and painting acrylic


#1

This is probably obvious to most people, but I have very little experience painting things (I’m not sure I’ve ever operated a can of spray paint), so I figured I’d document the trivial bit of experience I gained because it would have saved me quite a bit of experimentation.

I’m planning to make some control panels in the near future and I thought that black acrylic with white lettering would be nice. So I wanted to find the best way to score or engrave and use the masking as a stencil. I could still fine tune this a bit, but I’m getting decent results after a number of tries (left side):

My best results came from an engrave at speed 1000, power 20, vary power, min power 20 (well, 19.8), 340 LPI. The goal is to just blow away the masking without making a deep engrave, otherwise the paint won’t get down into it. Then I sprayed it it with this stuff:

My painting was sloppy and rushed, so I’m pretty sure I could get nice crisp edges by taking some time. Those are very thin features: just 1 point around the outside edge. Scoring was not successful: I couldn’t find a power/speed setting that could cut the outline of a 1pt line while leaving it intact.


#2

I’ve been using acrylic paint and an art brush and have been getting good results as well. I’ll have to try the spray.


#3

A brush might have gotten into the crevices better on the deeper engraves and scores. I brought a bunch of stuff back from the craft store today so I’m slowly working may way through it.


#4

They make syringes for paint. https://www.amazon.com/Precision-Applicators-Dispense-Pack-Rockler/dp/B01GWCVBKW/ref=sr_1_1?ie=UTF8&qid=1506900339&sr=8-1&keywords=paint+syringe

You just fill with paint and squeeze as you move the syringe to let the paint flow into the engraved areas. Some people will use a toothpick to help even out the paint.

I’m sure you can find them cheaper since these are Rockler brand.


#5

Just finished up a project using acrylic paints on engraved acrylic. Had the best results removing the masking, floating the paint into the engrave, and then wiping off the surface.

It was critical for this one to get really crisp lettering, and the first pass painting over the masking didn’t work very well with that kind of paint. It tended to dry and tear unevenly when the masking was removed.

Might try those syringes sometime.


#6

You might want to try using Black on Clear Reverse Laserable acrylic from Innovative Plastics Inc. It’s clear material with a thin black coating on one side, you laser away the black. Inventables part No 30430-01

The front/finished side of the clear material is actually a nice matte finish instead of high gloss, and it makes a super nice control surface.

You might also try rolling your own. Paint the “back” side of clear acrylic black then laser your design into the black. You can then paint white into the engraving on the back and the front will still be smooth and wear-resistant.


#7

Yes, Perfect description. We call it “reverse engraved”. In our shop we do this with a rotary engraver using Gravoply reverse engrave material. Then we paint the letters / text with an acrylic paint.


#8

I’ve seen videos where Lacquer paint lasers well.


#9

I would call that there a solder flux dispenser.


#10

A friend also said you can use Sugru to press into the depressions. (It’s an epoxy putty that you can get on Amazon) Don’t know personally if it’s any more resilient, but as an epoxy it might be. Sugru also comes in multiple colors. (She initially made the suggestion for putting into old range knobs that have had their color worn out over the years.)


#11

Sugru is great if you want something to have a rubbery feel, like grippy knobs. I wouldn’t call it an epoxy though ;p
Maybe a rub n’ buff compound would work?


#12

True, after a little more research it appears it’s more silicone based than epoxy. I’ve heard good things about Rub N’ Buff and look forward to trying it.


#13

Couple suggestions…there are a few others that have also done this sucessfully this way…

Or…you could use sign plastic like Rowmark. It comes in many colors and has a thin layer of color over a core. Etch off the top surface and expose the core. This was a recent job I did for United Way. 30 plaques. Marble blue with white core.


#14

Thanks for the example. I’ve looked into those kinds of things and I think I may have some samples on the way. Rowmark makes many products so if you can be more specific about what worked for you, that would be great. I think my employer uses some of these for signs around the office, and I’m considering the prank possibilities of relabeling conference rooms…


#15

They make 2 types…one for laser, one for rotary (this can have abs and or pvc as the top layer and does NOT laser well)

Heres a black surface with white core. Lasermax from rowmark.

http://www.johnsonplastics.com/rowmark-value-series-lasermax-black-white-1-16-engraving-plastic


#16

My very limited experience says that any thick layer of paint that goes down into an engrave will shrink and crack, much like joint compound or spackle. So very shallow or multiple layers or whatever.


#17

that goes for most paint, most of of the time.


#18

I’m late on this thread, but Sugru is really a Silicone base, wonderful stuff, use it all the time to repair cords, knobs, etc.


#19

So, I’m trying to learn here-- can you not paint, say, a white acrylic sheet with black paint and then laser engrave the paint away, exposing the white acrylic underneath? Or even mask on top of the painted surface so that you get a nice crisp edge to your engraving? I saw the post about reverse etching and etching on top but painting bottom, but what about painting and etching both on the top side?


#20

I don’t understand what you’re getting at here. The crisp edge would come from the laser as I read it. In general, painting over masking usually leads to issues with the paint bleeding/wicking up under the masking.

As for painting and then etching away the paint with the laser, yes that should be doable. I haven’t read or seen anything that would indicate some sort of inherent problem with this approach.